I bought this old army trailer and it came with a bullet vise as a bonus. the problem is it hasn't moved in years. The main screw came loose, moves about a half turn, but the dynamic jaw is stuck. I tried tapping on it while turning- no luck. I've been putting kroil on it and letting it soak in handle up position, but the oil doesn't even soak away. Looking for ideas. Heat? Open back up and spray? Let soak more (only been soaking for a day)? Any Ideas, looks like it is worth saving.